Clamp screw and nut for a tucking knife



Oct. 18, 1938. A, G'ELLLJVIAN 2,133,812

CLAMP SCREW AND NUT FOR A TUCKING KNIFE Filed Feb. 4, 1957 Fig.1.

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ATTORN EY Patented- Oct. 18, 1938 UNITED STATES PATENT OFFICE CLADIP SCREW AND' NUT FOR A TUCKING KNIFE This invention relates to new and useful improvements in a clamp screw and nut for holding the arms of a tucking knife in adjusted position.

The invention has for an object the construction of a knife as mentioned which is characterized by the fact that it has an arm adapted to be pivotally mounted and a blade with a straight edge over which the material to be tucked may be folded, and said blade being connected with the arm in a novel and advantageous manner.

More specifically, the invention contemplates connecting the blade and arm with each other by the use of a groove and tongue arrangement and providing a single clamp screw which may be opened to loosen the blade and arm so that they may be adjusted, or which may be closed.

Still further the invention proposes an arrangement by which the clamp screw is made of several sections and arranged so that the head portion 30 thereof may be released when desired to eliminate the necessity of opening the screw. Thus, additional convenience is provided for adjusting the tucking knife.

For further comprehension of the invention,

35 and of the objects and advantages thereof, reference will be had to the following description and accompanying drawing, and to the appended claims in which the various novel features of the invention are more particularly set forth.

30 In the accompanying drawing forming a material part of this disclosure:-

Fig. 1 is a plan view of a sewing machine equipped with a tucking knife according to this invention.

35 Fig. 2 is a plan view of the tucking knife per se.

Fig. 3 is an edge elevational view of Fig. 2.

Fig. 4 is a bottom view of Fig. 2.

Fig. 5 is a transverse sectional view taken on the line 5--5 of Fig. 2.

L0 Fig. 6 is a view similar to Fig. 5 but illustrating a modification of the invention. A

The tucking knife, according to this invention, comprises an arm l0 adapted to be pivotally mounted at the point II on the table [2 of a sewing machine l3. This arm is associated with a blade 14 having a straight edge M and also having a stem portion M slidable in a groove H1 in the arm H). A clamp screw I5 is associated with the stem and arm for holding these parts in relatively adjusted positions.

The full line position of the tucking knife, shown in Fig. l, is the operative position in which cloth material, indicated by the dot and dash line it may be folded over the edge of the tucking knife and fed to the sewing machine. The dot 3 Claims. (Cl. 85-5) through which the pivot element II passes to pivotally mount the arm upon a sewing machine table. The blade M has its outer extremity l4 bent downwards to engage the top face of the sewing machine table so that the goods which is being operated upon will merely slide over the tucking knife. The opposite edge of the blade I4 is formed with a projecting finger portion M adjacent a hollowed area M These parts are arranged so that the material which is being tucked, is guided to a close position to the operating needle of the sewing machine.

The stem portion M is formed with a slot I! through which the clamp screw passes. The groove It! is formed by merely recessing a groove into the top face of the arm It). At the area where the groove is formed the arm II! has a widened portion I0 This widened portion is imprinted 0r inscribed in any other manner with a scale I8. A line [9 is formed upon the stem l and cooperates with the scale to indicate the positions of the blade M.

The clamp screw l5 has a large and fiat head I5 It has a screw portion 15 extending through the slot l1 and through an opening in the arm II]. A nut 15 threadedly engages on the screw portion l5. A friction washer I5 is interposed between the nut I5 and the bottom face of the arm I0.

To adjust the blade 14 it is merely necessary to pivot it to an inoperative position as shown in Fig. 1 and then to turn the nut l5 to loosen the clamp screw. The blade and arm may then be relatively adjustedas required. The nut I5 is then tightened.

In Fig. 6 a modification of the invention has been disclosed which distinguishes from the prior form in the fact that the head of the clamp screw may be loosened to release the blade, in addition to the fact that the nut may be loosened for the same purpose. There is therefore a choice for loosening the parts.

More specifically, according to this form of the invention, the clamp screw has a head portion formed with a recess 26 into which a headed shank 21 engages. A resilient washer 28 is interposed between the base of the recess 26 and the head of the shank 21. Several pins 29 are mounted in the head 25 and extend into the recess 26 and engage against a shoulder 2! of the headed shank 21. This shoulder is formed with cam cutouts 30 arranged so that in a certain position of the head 25 the pins 29 are aligned with the cutouts and then the head 25 is loose, and in another position the pins 29 straddle the cutouts 30 and engage beneath the shoulder 2'! and then the head 25 is tight. The shank 21 passes through the slot I! in the stem M It also passes through the opening 20 in the arm I and threadedly engages the nut l. There is also a friction washer between the nut and the arm. The top face of the nut 25 is formed with a hollow portion 25 adapted to receive a thumb.

As shown in Fig. 6 the parts are clamped together. When required the head 25 may be slightly forced downwards against the action of the resilient element 26 and then the head 25 turned to align the pins 29 with the cutouts 30. The blade 14 and arm ID are then loose and may be adjusted. They may be re-tightened by turning the head 25 to cause the pins 29 to ride beneath the shoulder 21 The blade and arm may also be loosened by operating the nut I5.

While I have illustrated and described the preferred embodiments of my invention, it is to be understood that I do not limit myself to the precise constructions herein disclosed and the right is reserved to all changes and modifications coming within the scope of the invention as defined in the appended claims.

Having thus described my invention, What I claim as new, and desire to secure by United States Letters Patent is:- r

1. In a device of the class described a clamp screw and nut for holding the arms of .a tucking knife in adjusted positions, comprising a headed shank portion and a head portion, the head of the shank portion engaging into a recess in said head portion, pins on the head portion engaging against a shoulder formed by the bottom face of the head on said headed shank, said shoulder having cam cutouts formed radially therein and into which said pins may engage for releasing said head portion, and a resilient element interposed between the base of said recess and the head of the shank.

2. In a device of the class described a clamp screw and nut for holding the arms of a tucking knife in adjusted positions, comprising a headed shank portion and a head portion, the head of the shank portion engaging into a recess in said head portion, pins on the head portion engaging against a shoulder formed by the bottom face of the head on said headed shank, said shoulder having cam cutouts formed radially therein and into which said pins may engage for releasing said head portion, and a resilient element interposed between the base of said recess and the head of the shank, the outer face of the head portion being recessed.

3. In a device of the class described a clamp screw and nut for holding the arms of a tucking knife in adjusted positions, comprising a headed shank portion and a head portion, the head of the shank portion engaging into a recess in said head portion, pins on the head portion engaging against a shoulder formed by the bottom face of the head on said headed shank, said shoulder having cam cutouts formed radially therein and into which said pins may engage for releasing said head portion, and a resilient element interposed between the base of said recess and the head of the shank, said resilient element comprising a rubber disc.

ABRAHAM GELLMAN. 

